Disconnect switch



' 4DIsc'oNNEcT swl'rcnv v Filed April 16, 1936 s sheets-sheet 2 INVENTORl W///////////////////////////I bution system,V and intliislserviceilare sljecte'd to n a number ofw very exacting.voperational require` j i ments, someoiwhich are conictin'g'in nature. Inthe interest 'of safety, it is practically vi'rnp'erative thatdisconnectinglswitches shall sl'ioyfxr fa visi- Y yble breaksinthecontrolled circuit`wheninthe Y' open position. 'Ordinarily this' means"that 'the devices must be air breaksWtches. and as a, result,

Patented Nov. 15, 1938 4Westinshoiue Electricsz lilnnufactui'ing'`Company, #East Pittsburgh,

1 Y Pennsylvania implicationA aprirla, isssgserisl No. 54,108 f l 15Gummi.l (CL 20114-48) connecting switches.

i Devices of this type are utilized' primarily for interconnectingV andfor isolatingportionsof ahigh'voltage transmission or other powerdistrithe switches are subjected'to all types of weather conditions.vDisconnecting'switches are operated l but; infrequently, yet whencalled upon theymust' be Vcapable of ,y opening the` controlledcircuitdespite corrosion, iceA or sleet yforxnation,orfthermaticallycapable ofcutting through oxidation t tand corrosion inorder toassure low resistancejj" .contacts throughout' their operative jlives.`As

opposed to these operational requirements, comsystem.

1 which ,are used The principal; objectief. the presentinvention,

necting switch. which shall be capable of'` satisfactorilymeeting theabove stateclb` requirements', 'l i The particular structure'`utilizedfor 'accomplish ing this object ofthe invention is animprovement and a further refinement of the 'switch disclosed ,in myPatents Nos. 2,039,059 and y2,067,659 issued `breal: switch, either ofthe vtwo insulator ori'of the three insulator .type, an`d in' applyingthe'princiy ples disclosed in "the"` above-mentioned patents objects ofmyfinvention;`

The present inventicmny as to a sidebreakswitch Iaccomplishanother orthe l a'.unitarymemberyhich' isfprovide'd with a toothed portionforengaginga similar toothed( portion forming a part'of the stationarycontact means in .order to permittl'ie `mechanical inter-l merciallysuccessful disconnecting switches must Abe relatively low incostiduetothe large numbers' on even a small transmission therefore, is ,toprovide a simple, reliable discon" 'dol'thestructures disclosedint'heabovecited patents,` utuizes ai parallel blade construction., vOneof the blades is the details 0f the Cooperating contact portions of Fig7; and

into engagement withthe stationarycontact. yBy this'operation thecooperatingtoothed members are causedto'engage each other, therebypme#chani'callyinterconnecting the rotatable insulator and the stationaryinsulator; Alost'motionconnection intermediate the` unitary `blade andthe rotatable insulator-allows the further rotation of that insulator,-which v'rotation causes the articulated blade element gto". be movedlongitudinally andy-at thes'ame" timefl'aterallywith respect to thefunitarybladelelement. The combined4 result of l'this i."ngitudinal:andl lateralmovement is to providefahigh pressure wipingengagementbetween 4 the cooperating portions of the blade elements y I[and the-contact meana f' conditions.. Further,`,thedevice s shouldbeauto- A further object of the-present invention to 'generally`simplify the structure ,of switches o'f "this typeby reducingthe:.numberoi; partsjre- ,quiredv to the minimum'and toxincreasethereliability in operationfofthestructures.

Otherobjectswill be apparent in the iollowing 'description ofthe twopreferred-.embodiments of ythe invention; Referring totthe drawings,

Figure 1 lis a side elevationalfview'of a three insulator side f breakdisconnecting vswitch utilizing the features ofthe presentinvention,

Fig. 2

is a plan view'ot the structure, shown in F1a-1,-

`rFig.; 3 is an enlarged fragmentary Dian view f similar to Fig. 2,showing they switch in the parv tiallygopen position, y

Fig. 4 is a Iragm'entary'elevational view-,sinnlar insulator and theother'endoi which isconnected i f to the unitary* blade'member adjacentthe unsuplaortidexidfthereof.` rDuring the operation oi' 4the switch,the unitary blade element is'swung toQFiggl."showing-'th'e.relativellpositlon of,- the blade elements and thecooperating stationary ,Contact .when the switeh 'is 1n the fpartiauy.open position, Y

1 'Fig.` 5 isafragmentarysectionalview showing the. details of the lostmotion lconnection between .the unitary blade elementV and therotating'1nsu flator,` y

111g. 61s fragmentary secnonai view showing the stationary`contactfmeans and the blade ele..

Fig. 9-is a sectional view taken on .line

The three insulator switch illustrated in Figs'. 1

through 6, inclusive, includes a base i which'is preferably formed froma piece of channel iron.l

a pair of stationaryinsuiators 2 mounted on said base through the use'oi' a pair of suitable spacers 3, and a rotatable insulator l mounted onthe base intermediate the two stationary insulators.

A ball bearing connection 5 permits the rotatable insulator I to bemoved freely with respect to the base. A stationary contact assemblage'I is sup-' ported upon each of the stationary insulator columns 2 and ablade means l movable into and out of engagement with these contactmeans is 'sup-f' ported upon the rotatable insulator l.

- Each oi the stationary contact assemblages 'l includes a jaw member lwhich is cast inteiral with the base portion i0 of the assemblage and anoutwardly projecting portion ii which is utilized as'one of theterminals for the switch.

A The upper of the two inner surfaces of each of the jaw members 0 ismachined into a knife edge form as `shown at I3 in Fig. 6 forcooperating with one of the Itoothed portions I4 of the blade assemblageland the lowersurface of each of i the jaw contacts is machined so as todene a soo ` of the cooperating blade curved surface as shown at Il forcooperatlngwith .one oftheccntact portions il of the blade as- Msemblage. The outerportion of each of the law` contact portions of theblade means and the contact jaws and toelfect thegoperlttiony of themeans for. mechanically interconnecting the spaced stationary insulatorcolumns. `The unitary blade element i1 includes a pair of ytubular blademembers- ILeach oi which is rigidly afcap member 2| fixed to" acentrally `positioned n for the which-is bolted to the support member 22blade assemblage, which member is, in turn, boltl of the rotatableinsulator 4. The is movable with respect to the 22 through a-deiinitelyrestrictv spring 2| is provided for ed to the cap 23 capv member 2isupport member ed distance and a coil biasing the cap member 2| and theblade por-v tions supported thereon to a predetermined position `withrespect to the support member. The

" toothed portion il for engaging the toothed portion I3 of thecooperating contact jaw is brazed `or otherwise rigidly aiilxed to theother end of each of these tubular blade members i9.

As is-shown particularly in Figs. 1 and 4, the support member 22 for theblade assemblage is provided with a pair oi'outwardly projecting crankarms and the inner end lof each of the otherl two tubular blade membersil is pivotally aillxed to each of these crank members. theresultantstructure comprising a pair of articulated bladeV elements. The contactelement ii, substantlallysimilarto the toothed members il except thatthe lower surface thereof is ilat, is affixed to the outer end of eachof the blade elements i8, and the unsupported endf of each of thearticulated blade elements I8 is mechanically connected to theadjacentunsupported end of swingable movement likewise supported the- 4 but.which are lrlovable'in-A the unitary blade element n by a pair or ne Ylinks 21. one end of each of these links being pivotally joined to oneofthe members by suitable pivot pins.

It will thus be seen that the blade assemblage comprises in effect onesubstantially rigid blade ement which isg'provided with toothed`portions -for engaging'the toothed portions of both of the two contactjaws and a pair of articulated blade elements fastened at their innerend to' the rotatable insulator column and fastened at their outerend bysuitable tie links to .the unitary blade structure. The spring 2lintermediate the rotatable support member 22 and the cap member 2ibiasesthe several portions of the blade assemblage to the position shownin Fig. 4. 'Ihat is,

it biases the articulated blade elements IB to a position where thecontact portions it thereof are as'closelyg adjacent the toothedportions I4 of the unitaryblade'structure as is possible. Thisfacilitates the engagement of the cooperating portions ofthe blade meansand the contact jaws Q during the operationof the switch.

The switch is shown m me fully dosed-position portions i4 fof theunitary blade element Il and Vin Fig. 1. In this position, the toothedcontact `A,the plalncontact portions I8 of thearticulated blade elementsVIl are held into intimate engagement with the cooperating portions -ofthe contact jawsl. The rather considerable length of the blade elementsI8 and the positioning of the link members 21 closely adjacent the outerend `of the blade assemblage allows the inherent' resilience of theblade members to be utilized as the source of contactpressure betweenthecoof the blade assemblage and To openthe switch, the rooperatingportions the contact jaws.

tatable insulator I is turned in a clockwise direction (Fig. 2) viromthe position shown in Fig. l to the position shown in Fig. 4'. Thisclockwise rotation actuates each of the articulated blade membersthrough-the crank arm's 2B -joined thereto, and moveseach of the blademembers longitudinallywith respect to the unitary-l blade element i1.The presence of the links 21 causes the contactportion Il to move in thedirection of the toothed -portion Il and thus decreases the spacebetween those portions so as to permit leasy disengagement of theportions from the contact jaw 9. lThe swivel connection between the capmember` 2| and the support member 22. allows this longitudinal andlateral movement yof the contact portions I6 to take placewithout moving.the unitary bladestructure i1. When the articunormal fully openposition ofthe switch.

To close the switch the central insulator 'l is rotated in acounter-clockwise direction so as to swing the blade assemblage from theopen circuit position to a position where the toothed Vportiers. u ofche unitary blade' element l1 eno gage the cooperating portions i3 ofthe contact jaws. The biasing spring 24 causes the blade assemblage toremain in theoposition shown in Fig. 4 during this portion of closingoperation. As soon as the toothed portions Il engage the closed end ofthe jaws 9, further rotation of the unitary aisaovv blade element l1 isprevented and a subsequent rotation of the central insulator! will causethe articulated blade portions il .to be moved from the position shownin 113.4 to the position shown in Fig. 1. This movementbi!vthearticulated blade elements `Il causes each ot the blade portions Ilthereof to be moved longitudinally and laterally with respect to theunitary blade element l1, and the combined result of this longitudinalyand .lateral .movement isito produce a high pressure wipingengagementbetweenthe cooperatingcontact surfaces Il ot the contact jaws i and the`contaEtj portions i of the two, ...articulated blade elements.v Thelateral movement of the articulatedblade elements Il alsoenects anintimate engagement: between Athe toothed portions Il ofthe contactiawsl and .the

` to't'ithedportionsil of the unitary blade element rotatable insulator33. 1

I1, thus assuringv that the two `spaced stationaryinsulators I. shallberigidly interconnected'when the switchis in4 thegfully closed position..j j j' j By interconnecting` the switchesl the spacedstationaryinsulatorsl. during the switch closing: operation, aresubjected to substantially no canti-1 lever-stress.. This permits theuseof high pressure contacts witha 'wiping .action and in addition makesi'or a much more rugged structure.

Figs. 7 through 9 illustratefanembodiment oi -my invention as applied-to4a two insulatorgside break switch: The various structural elements tof. thedevice are mounted upon a base litwhich, "simllarto .the .base Iof vthe previously described structure, mayfbe of channel iron andinclude j a stationary insulator. column lihaving a sta-` tionarycontactmeans 32 supported thereon and p a rotatableinsulator column 38supported upon thebase by means-ofy a bearing Il. u assemblage islsupported upon and adapted," to be actuated in response to the rotationof thef The stationary contact assemblage 3 2 comprises a jaw member4 31which is bolted to the p. Theblade assemblage 8l comprises a pair o!vbladcelements 3l and Il. `I'he element 3l is a stationarysupportinginsulator 3l therefor. this jaw ,beingv substantially the sameas the jaw members i in thefstructure just descijbldtnd has a knifeedgeI Ifupper portion and a curved `-llower portionzil. as is 'shown in Fig.6. f

unitary member and is rigidly ainxed at one end to asubstantiallylU-shaped support III, adapted `Ato engage a bearing pin,"which projects upwardly from" acast Aframe l2. .The frame l2 is boltedto a ycap of the vrotatable insulator 33,

asis shown particularly in Fig. 'l.l The outer end of the blade member38 is provided with a.v toothed portion for engaging thetoothed por--`tion i8 ofthe cooperating contact jaw 31. l

' .The blade element I9 is somewhat shorter the element 3l `and issupported uponl en out-v-f wardly. projecting crank memberll castintegral '.with the frames! by means'ofa pivotlpin Il.

" The other endoi.I :the-bladefmember-.II is pro-,1l vided withacontactportion .forjengaging the cooperating portion Ilof the contact,jaw I1 and isfmechanlcally connected to the outer end joi':the.bladeelement il by means of` a link` or pair o! links and twopivot pinsll.

A cylindrical member l2 is journaled upon the shaft portion 4I of theframe 42 4and is provided with an outwardly projecting element 53 forsupporting one oisthe Vterminals of the switch. VA"

ilexible shunt 54 connects the cylindrical mein--V ber l2 with the bladeelement. and this element, in turn, isconnected to theblade elementThe.'operation A blade il Through 'thisarrangement the terminal at Il ofthe switchis free to turn `with respect to the rotatable insulator 33during the operation of the device. .l 'nie other. or the switch isformed by an outwardly projecting element vI'l i cast integral withthecontactjaw 31.

A coil springnll :which ispositioned intermediate the u -shaped supportand the crank portion 4I oithearticulated blade `element '3l' 1 .3 n bymesmo: a. sectas pair of shuntsfsl.

serves to biasthe 'blade assemblage toa position substantlauyas rthat*shown in Fig.V 4;.tnat is,` .to a position `where -thecontact portion Itof i the articulated blade yelement Il has been movedas far as possiblein the direction ofthe toothed vportion Il of the unitary blade elementIl. rI lils arrangement, as'has been explainedinthe fore-- going,faeuits'tes the entry or the.; unsupported end ,foi the bladeass'e'inblyirlto the cooperating contact Jaw 31.

of this embodiment ormyfin;

ventionis substantially the same as the g'tion of the three insulatorswitch previouslydescribed. .'rne device is shown in the closed tira.

-cuit position in Fig.5'l.` To open the switch, ythe insulator Slisrotatedy in a clockwise direction (Flg..8), thereby causingthearticulated blade.

element n t'o b e moved substantially to the position shown infFlg.- 4.The coil spring if acts yto biasthe blade element 38 intoengagernentwith the `contact Jaw Il du'rlngthis longitudinal andlateral movementofthe contact portion foi the blade element l. As soon as the articu- Ijandthe entire assemblage is then swung as a"unit from the closed.circuit positiontol the opencircuit position which maybe'f90.- moreorll` lessgfromt'he position shownin Fig.' 8.

The closing. operation of the switch is'substantially the, reverse ofthe opening operation.

; The rotatable insulator 38' is turned so as to f swing theentire bladeassemblage from'the open circuitposition to a position where the toothedlated 4blade element 30 hasl reached they position shown in Fig. 4, therotation of therotatable 35 insulator `is transmitted tothebladeeiement` portion ll of the blade element 30 engages the Jcooperating toothed portion of the jawelement 31. The biasing spring llby holding thefblade elements in the position shown in Fig. 4, assuresthet'tne contact and toothed .portions 4s and l45, respectively; of thatassemblage shall be'read- 1 ily moved into'the contact jaw Il..` Uponfurther rotation ofthe' rotatable insulator Il the articulated' bladeportion Il ismoved from the co1- lapsed tofthe extended position, thusmoving lthe blade member longitudinally and laterally with respectitothe .blade .element ",@this movement v `beingcontrolled by the links Ilconnecting the `plain contact and-the toothedfcontact portions Il and;`ll6=, respectively, oi' the blade assemblage -ati .their unsupportedend. The combined result produce fa' high pressure wiping engagement 'ofthe cooperating contact portions lland' i5 oi' l the blade 3l and thecontact jaw `I1 and to cause the cooperating toothed 'contact portions"and- I3 of those structures to be forcedI into intimate 'engagement Witheach other. ff' 'l c.

l By utilizing a `toothed element having.` a plurality of separate teethas the interconnecting means for the insulators Il and n, a structure isprovided which is capable of automatically adjusting itself` to a verysubstantial amount offrelative displacement of the stationary and therotatable insulators. Satisiactory operation of the interconnectingmeans under extremely adverse conditions isthus assurred. o

From the foregoing it will be seen that I have ydescribed twoembodiments of a novelform of side break disconnecting switch whichpossess numerous advantages 'over thestructures heretoiore .known to theart. More particularly, I have disclosed a double break three insulatordisconnecting switch which isprovided with'means for rigidly.interconnecting the three insulators during the operation of the -switchso asto impart rigidity and strength to the device, and whichinterconnecting means is capable of automatically adjusting itself to avery substantial amount of relative displacement o! the severalinsulators of the'switch. Further, I have shown how this interconnectingmeans; can be applied to a switch structure which utilizes cooperatingcontacts adapted toengage each other with a high pressure wipingengagement.

` I have also disclosed how the above features for automaticallyinterconnecting the rotating insulator and the spaced stationary'insulator may be applied to a two insulator side break disconnectingswitch with all of the advantages resulting in the case of thethreeinsulator switch.

Both of the structures are relatively simple in design, they are easy toservice andare not unreasonably costly.

While in accordance with the patent statutes, "v

I have disclosed in the foregoing thedetails of certain preferredembodiments of my invention, it is to be understood that many of thesedetails are merely illustrative and variations in their precise formwill be both necessary and desirable Y in certain instances. It is myintention, therefore, that the language of the accompanying claims shallbe accorded the ybroadest reasonable construction and shall be limitedonly by what is expressly set forth therein and by the prior .art

Y I. claim the following as rnyinvention:y

1. In an electric switch, a pair of spaced insulator columns, contactmeans mounted on each of said spaced insulator columns, a rotatableinsulator disposed intermediate said spaced insup lator columns, a blademeans normally supported on said rotatable insulator for movement intoand out of engagement with said contact means, and means responsive tothe rotative movement of said rotatable insulator for causing said blademeans to engage said contact means with a high pressure contact, .said`bl-ade means having contact portions adapted to interlock with saidcony tact means in one of a plurality of predetermined positions forinterconnecting said spaced insulator "columns prior to movement of saidblade means into high pressure engagement with said contact means. l

2. In an electric switch, a pair of spaced insulator columns, contactmeans rigidly supported on each of said insulator columns, a rotatableinsulator column disposed intermediate said spaced insulator columns;and a blade means normally supported upon said rotatable insulatorcolumn andr movable, in response to the rotation there-v of, into andout of` engagement with said'contact means, said blade means and saidspaced insulator columns having cooperating toothed members forrigidlyinterconnecting said spaced insulator columns whenv saidinterrupter is in the closed circuit` position, and said toothed memberslbeing disposed longitudinally of said blade means o for engagementwitheach other irrespective of the displacement within certain limits ofsaid thereof movable into and out of engagement withj said contact meansin'response to rotation of said rotatable insulator, and meansresponsive to the rotative movement of said rotatable insulator forcausing said contact portions of said blade means to engage said'contact means with a wiping action, said blade means having othercontact portions adapted to interlock with said contact means in one 'ofva plurality of` predetermined positions for interconnecting said spacedinsulator columns prior to` movement of saidinrstnamed contactportions'intowiping engagement with said contact means.

4. In an electric switch, a pair of spaced insulator columns, contactmeans mounted on each oflsaid insulator columns, a rotatableA insulatordisposed intermediate said spaced insulator columns, and a'blade meanssupported upon said rotatable insulator and movable into and out ofAengagement with said contact means in response to the rotation of saidrotatable insulator, lsaid blademeans including means for'rigidlyinterconnecting said spaced insulator columns during the .circuitclosing operation,said interconnecting means including cooperatingtoothed memb'ersat least one of which'has a plurality of teethto'provideffor cooperative engagement lof said members in any one of aplurality of positions, a contact portion for engaging each of saidconf` tact means, and means for causing each of said contact portions tobe moved, with respect to the contact means with whichA it vcoactsduring each switch closing operation so as to eiect a high pressurewiping engagement between'each of said contact portions and saidAcontactv means.

5. In an velectric switch, a pair of spaced insulator columns, contactmeans rigidly supported upon each of said insulator columns, a rotatableinsulator disposed intermediate said spaced insuv. lator columns, andconducting means supported upon said'rotatable insulator column andmovable into and out of engagement' with said contact means, in responseto the rotation of said rotatable insulator, said conducting meansincluding a plurality of blade elements, one of which comprises arelatively rigid bridging member supported on said rotatable insulatorfor swingable movement about the axis vof rotation thereof, and theothery of said blade elements comprising a blade member, said bridgingmember and said'contact means being provided with cooperating toothedmembersadapted to en- 'gage each other in any onevof a-plurality ofpositions for rigidly'interconnecting said spaced insulator columns whensaid interrupter is in the closed circuit position, said blade memberincluding a contact portion `which engages each of said contact means,and means for 'moving said blade memberduring each closing operation ofsaid switch into a-high pressure wiping engagement with said contactmeans.

6. In a side break electric switch,"a stationary contact means, arotatable insulator and a blade means supported thereon for swingablemovement into and out of engagement with said stationary contact meansin response to the rotation'oi said-rotatable'insulaton said blade means,response` to the rotation `ofsaid rotatable 'insu-v i lator betweensaid: predetermined angularfpositions forimoving lsaid articulated blademember longitudinally and independently'oisaid unitary lis` l f thellongitudinal movement `of saidf'larticulated blade member for eiectinga high pressure wiping engagement "between `the 'cooperating contact'A*j `members.` l Inl a side :bre

tween predetermined `angular positions, anvarticulated blade'imember,pivotally aixed atone end to said rotatablelinsulator, a linkage joining`the other end-offsaid articulated blade member' tdsaid unitary blademember adjacent the supported end` thereof, and means operable in blademember, said-linkage being responsive-to portionslof said contact meansand said blade' a lase esta 'statmnary l contact means,` `a;rotatable-insulator and a blade lmeans supported `thereon for swingablemove-2*]` mentintoiand `outjof engagement with said"sta`" 25.-

\ 1 `tionof said;rotatableinsulator, saidfblade means i 3 including-a*unitaryblade memberfsupportedffon saidzrotatableV insulator forrelatively rotatable`--' e movementabout thepivotal axisf thereofbetv'veen'Y member adjacent theunsupported Lend' thereof; `andmeansnoperable in 'responseto therotation of said rotatableinsulatorbetweenfthe predetermined angulanpositionsjfor moving-said articutionary,contact means in` response tothe r' o'ta4 predeterminedangularpositions, an articulated blade member pivotallyxaiilxed at one endtosaid@ insulator, a.A linkage Vjoining the -other end offsaid* latedblade member ylongitudinallySand inde- 1' tatable insulator, a blademeans comprising a, v

pair of blade elements supported upon saldrotatable insulator andswingable into and outof engagementlwith said contact means in responseto the rotation thereof, one of s-aid blade elements being rotatablysupported upon said rotatableinsulator for relative rotative movementabout the pivotof said insulator, a mechanical. linkage connecting theother ofsaid blade elements at its outer end to said iirst mentionedblade member, a crank member rigidly alxed to said rotatable insulatorand pivotally connected to the inner endof said other blade` element,said support means for said :first-named blade ele, ment permitting therotation of said crank member independently of said first-mamerginblade`ele lment during the final stages of each closing operation of saidswitch, said last-mentioned blade element being movable longitudinallywith respect to said `first-mentioned blade element in' response totherotation of said crank during the circuitclosing operation,saidmechanical linkage being actuable in response to thelongitufdinalmovementof said'blade member for causvincluding afunitaryblade member supportedon fV said rotatable insulator for relatively"rotatable .movement about `,the ,pivotal axisfthereoi'f-be- 'lingthecontactyportionb! at. least lone of said bladeelements toengage'the 'cooperating contact portionotsaidcontactmeanswith a highpressure wiping engagement." l 9. In anlelectricswitch; a stationaryinsulator column; a Contact' means-mounted thereon, arotatableinsulator, meansz;comprising a pair of bladeelements'sulpported' upon said rotatable insulator and' swingabler1x1/response tothe rotation thereoi' 'finto and "out ofengagemfent'with said contact means, lostf-rnotionimeans operatively' coupling oneo-o'f'isaidi elements? and said 'rotatable insulator, thewhenbfjsa1-1'.tieneV elements being mechanicallyconnectedg'at itsfouterend to :said tlrstimentioned blade *element arid pivotally connected iat its inner endtb a crank member 1` means having; cooperatin`g`'toothed portions adapted toengag'e eachfother `ina'ny'one of a.plurality of positions fior positively' interconnect?ingsaidistationary insulator column and said ro` tatableinsulator{colummwliensaid interruptor is nffthe closed"ci'c'suit'position` said `lastrnentioned A"blade :element*beingmcvable'longitudinally with --res'pectto"said nrst=mentioned bla'cle element inresponse ftoyniovement "of s'aid crank member yrig' idlyiafliced ofsaidrotatable insulator column contact-means `arid*s aidfblade lmeans 'andtoeffect articulated blade member-to'saidunitary blade" i rigidly-` amies*to Y said rotatable" insulator, said the'fcooperative*engagementof saidinterconnectl fing 'means during; each operation oi "said switch. 1 l0'.an'electric-switch including-acontact, a rotatableactuating@insula/tor;Li?l switch blade having "a contact atl one end:thereoi for engaging the "first said contact,` s a pendently foffsaidunitary blade memberfsaidf" 'sw ii'. 'cl 11` blade 'being piv-`otallymounted on said rotatable insulator and being actuatedthereby,"`theI pivot'of'the switch vblade being coincident with theaxisof rotation of the insulator and permitting rotation of` theinsulator relative Vto the blade, spring means be-l 4tween the .bladeand the `insulator tending to maintain them in a predetermined angularposition with respect to oneanother, said rotatable insulator beingrotatable relativerto said bladey against the biasof said spring afterengagement of the contacts tomovevthecontacts into flnal high pressureengagement,A and theengageable surfaces' of said. contacts havingcooperating switch blade with said first contact in any one of aplurality of positions as determined by the displacement between saidfirst contact and said 11. InV an electric ber, "`a. linkagejoiningsaidblades adjacent `said contacts, a rotatable insulator forpivotally supporting said switch blades and for actuatingv them to openand closed positions, one of said switch blades being rotatably movablewith respect to said insulator between predetermined angular positions,and means responsive to the rotation of saidv insulatorbetween saidpredetermined angular positions for moving the other o tsaidswitchblades longitudinally `with respect yto said rstblade, saidIlinkage being responsivel to the longitudinal. movement of said switch`'blade for Acausing saidcontacts to firmly engage ysaidcontact member,at least one of said switch blade contacts and cooperating contactvportlon oi said contactf'memberbeing provided with switch,` a contactmembena' pair of switch bladesfeachliaving acontactfat onjexend thereofforengaging said contact mem-` 4toothed portions for positivelyinterlocking the bers "between predetermined angular positions,`

serrated surfaces for positively interconnecting the switch blade andcontact member.

12. In an electric switch, a'supporting insulator,v a contact membermounted on'said insulator,

a rotatable insulator, a lpair of blade members,-A

mounted upon'nhsaidrotatable. insulator and operable by the rotationthereof into engagement with said contact member, a linkage joining saidblade members adJacent the endvwrhich engages said contactmember, saidrotatable insulator be-` ing rotatablerelative to one o fk said bladememtl'ieother of 'said blademembers being longitudinally movable-withrespect tothehfirst said .blade member bythe rotativemovement of saidrotatable insulator betweenA said'predetermined'` angular positionsftoactuate lsaid linkage and f therebymove said blade `members into inalhigh pressure contact withsaid contactmember, and

.the engageablevcontact. surfaces ofA atv-least onel of saidblademembers andsaid lcontact member Y having cooperating toothed.bportionsyforgpositive# ly interconnecting, said insulators when,y the@switchis in the closedposition.

13. In an electric'switcna cuntactmember;` a pair of switch bladeseachhavingracontact; at;

one end thereof4 for engaging said contact meml, ber, a linkageVjoiningsaid blades adjacentsaid contacts, arrotatableiinsulatorjiorpivotallyvsup-A- porting said switch bliide s.l and for actuating`themto openandftoclosed positions,`one of*j said c switch blades' beingrotatably movable' `with Arespect to said insulator betweenpredetermined I angular positions, means biasingsaidfirst-namedblade toAa predetermined angular position'with respect tosa'id insulator,andsirieansr responsive d to the rotation o1 saidinsulator between` saidpredetermined angular `Apsitioifis .against said*` biasing means formoving the other of said switch 40' blades longitudinally with respectto said first blade, saiqiinkagebeing responsive tothey 1onrgitudinalmovementfoi witchblad,for l I said contact member.

causing said contacts to iirmly engage said contact member, at least oneof said switch blade contacts and-the vcooperating contact portionsVoi'said contact member being provided with ser- Aratedvsuriaces forpositivelyinterconnecting the switch bladeand contact member.

. 14.,In an electric -switch,'. a supporting insulator,.a contact membermounted on said insulator, a rotatable'insulator, blader means carriedby said rotatable insulator adapted to be swung into and outofengagementfwithsaid contact lmember 'by rotation of said rotatableinsulator,

and means responsive'to .the rotative movement of said rotatableinsulator for causing said blade means to engage -said contact memberwitlf'a `high pressure contact, said blade means having contact portionsadapted tofinterlock with said contact` member in one of a plurality ofpredetermined positionsl for interconnecting said support andsaidrotatable insulators prior'to movementiof said blade means into high:pressure engagement with said contact member.

v- 15. In an electric switch, a pair of spaced insulator columns, oneof'which is rotatable, acontactmember supportedupon the otherinsulator`column, a` pair of bladeelements carried by said .rotatable insulatorcolumn, said Vblade elements being adapted to be-movedinto'and out ofenfgagement with `said v,contact memberin response to rotation of saidrotatablef'insulator column, and means responsive rto theirotationofsaid rotatable insulator column for moving said blade relements intofinal high Dressurefiengagement -with said Acontact member, at least.one of said blade elements andsaidcontactm'ember having a yserratedcontact Aportion for interlocking engagement with eachI otherpinone of'a plurality of posltionsprior to movement :of said blade elements intofinal Ihigh pressureV engagement with :HERBERT J; enanas.

